Instead of using DC bias, the DPD operates at pulsed voltages: the applied voltage is switched from reverse to forward bias. This forward bias induces a large forward current after a time delay, so called triggering time, which depends on the light intensity. This way, we measure the delay time of the large forward current instead of the small photocurrent magnitude.
Because of the large output signal, ActLight claims that DPD needs no amplifier. It can be directly connected to digital circuits.
ActLight expects the first ASIC integrated with the company’s photodiode to emerge in 2019, indicating that there are two or three OEMs already taking a closer look."
